Needle board for needle loom



March 3, 1964 A. M. sMlTl-l n 3,122,815

NEEDLE BOARD FOR NEEDLE LOOM Filed Oct. 4, 1961 2 Sheets-Sheet 1 lll) A BY WOQM/QLMMJ ATTORNEY@ March 3, 1964 A. M. SMITH 1l 3,122,815

NEEDLE BOARD FOR NEEDLE LooM Filed oct. 4, 1961 2 sheets-sheet 2 ATTORNEY' United States Patent O 3,122,815 NEEDLE .SQARD FR NEEDLE LOM Alexander M. Smith Il, i321 Gwyn Ave., Elkin, N. Filed (Bet. 4, 1961, Ser. No. M23-49 4 Claims. (Cl. 28-4) The present invention relates to an improvement in needle boards for needle looms or the like.

In recent years and, particularly with the advent of synthetic fibers, there has been considerable development in the art of producing non-woven fabrics from batts or Webs of loosely matted bers. Needle looms have been heretofore used to orient the iibers of the webs, the needle looms being provided with needle boards having an array of needles which are reciprocated into and out of the batt or web. Usually there is subsequent treatment to the batt with suitable bonding agents to bond the bers together.

ln my copending application Serial No. 31,910, tiled May 26, 1960, and entitled Method of Needle Punching Fibers to Make Needled Fabrics or the Like, now United States Patent No. 3,090,196, issued May 2l, i963, there is disclosed an improved needle loom for orienting the fibers of a web of loosely matted fibers into controlled cohering liber entanglement Such as interlacing and terlooping. As disclosed in the aforementioned patent, by having the needles of the array of needles of the needle board adapted to penetrate the web at specific desired angles, it has been found that control of the interloopng and interlacing of fibers can be effectively accomplished.

Heretofore, needle looms employed wooden or metal needle boards or slotted strips for holding Shanks of an array of needles in a desired pattern. Special selected mahogany has been considered the best type of material for making needle boards, the mahogany having a thickness in the order of three-fourths of an inch to one inch. The holes for receiving the needle Shanks in the wooden or metal boards have been made by utilizing small drills, but such drills often led away from a desired course when drilling through the thick metal or wood board. rThis was not critical in past neediing operations and very little attention was directed to having every needle of the board accurately oriented with respect to every other needle in the board. VJhen the advent of synthetic fibers which led to the discovery that all needles in a pattern of needles must be accurately oriented with respect to each other to provide for controlled needling, the use of the thick wooden or metal boards has been found to be unsatisfactory for accurately holding the Shanks of the needles so that the needles have accurate orientation for a desired type of needling.

An object of the present invention is to provide a needle board made of a composite structure and capable of holding an array of needles in accurate alignment and orientation.

Stili another object of the present invention is to provide a needle board whereby needle alignment and orientation for an array of needles is simultaneously accomplished.

A further object of the present invention is to provide a needle board of lightweight and sturdy construction which is capable of withstanding stresses and strains encountered in continued use of the same.

Another object of the present invention is to provide a needle board which is made from composite parts, the holes in such parts being formed in such a manner as to provide for accurate orientation of an array of needles.

Ancillary to the preceding object, it is a further object of the present invention to provide `a needle board wherein the holes for receiving the needle Shanks in a desired pattern are simultaneously made.

Federated ll/iar. 3, i964 These and other objects of the present invention will appear more fully from the following drawings wherein:

FIGURE l is a fragmentary sectional view illustrating the :'irst step in making the needle board of the present invention;

FIGURE 2 is a fragmentary sectional View through a needle board made in accordance with the present invention;

FIGURE 3 is a fragmentary perspective view illustrating a completed needle board for a needle loom with a few of the needles inserted through the holes in the needle board and others omitted for the purpose of clarity:

FGURE 4 is a fragmentary sectional view illustrating a modified method of making a needle board according to the present invention; and

FIGURE 5 is a fragmentary sectional View of a needle board made in accordance with the method illustrated in FIGURE 4.

Referring now to the drawings wherein like character or reference numerals represent like or Similar parts and, more Speciiically, to the perspective illustration of FIG- URE 3, the needle board of the present invention iS identified by the numeral itl and is a rectangular parallelepiped shaped member having a plurality of rows of holes 12 therein for receiving Shanks 14:- of needles i6. While the needle board shown in FIGURE 3 has a plurality of rows of needles 16 extending transversely of the needle board l0, with the rows of needles aligned with needles in other rows, it is, of course, within the scope of the present invention to arrange the pattern of needles in a manner disclosed in my aforementioned U.S. latent No. 3,090,100 wherein the transverse rows of needles are staggered with respect to each other so that there may be more needles punching the web transversely of the same in each widthwise inch. By staggering the rows of needles to obtain more punching per Widthwise inch, the needles in a row may be spaced further apart. Any other desired pattern for the array of needles 1.6 be may be used, it being understood the invention pertains to the lignrnent and orientation of needles in the making of the needle board.

T he needle boards of the present invention have an overall width of approximately 8 to l5 inches and an overall length of approximately 60 to 160 inches. Such needle boards usually contain approximately 25C() to 70C() needles, the needle boards being supported in the needle looms on the ends of oscillating arms or otl er suitable oscillating structure. The weight or mass or" the needle board is of considerable importance because it determines the magnitude or" the force required to effect the acceleration and deceleration of hiah speed oscillation. By lightening the needle board, acceleration forces are reduced; power requirements, various structural stresses and bearing loads are correspondingly reduced. It is also necessary to maintain strength and rigidity in the needle board because of its tremendous size. It will be understood that such needle boards are used for producing continuous lengths of non-woven fabrics having widths of approximately 60 to 160 inches.

The needle board it) of the present invention is made 'oy placing two thin sheets of material is and 2i) together as shown in FIGURE l. The two thin sheets of material 1S and 20 have an overall size substantially equal to the desired size of the needle board but have a thickness in the range of .020 to .G62 inch. The sheets of material 1S and 2li are relatively stift and may be made from either plastics, such as Fiberglas reinforced epoxy resins, or metal, such as thin sheets of aluminum. While FIG- URE l shows the Sheets 18 and Ztl spaced apart slightly, this iS done merely for the purpose of illustration. The Sheets are originally placed together and suitably clamped in a contiguous relationship with one another and then a drilling apparatus comprising one or more drills 22 is used to simultaneously drill through both sheets to form the small holes 24. if a single drill 22. is used, a suitable template may be used to mark the topmost sheet where the holes are to be drilled, the template having a desired pattern for the Yarray oi needle On the other hand, the drilling apparatus may incorporate a plurality of drills arranged in the desired pattern and, if this is the case, then a plurality of holes may be drilled through both sheets of material i3 and 2@ simultaneously. It will be appreciated that ther sheets lil and 2t) are quite large and there are a great number oi holes 24 drilled therein. The drilling apparatus containing a plurality of drills arranged in the desired pattern may be used to drill a portion of the total number oi holes to be drled, it being understood that the Sheets could be suitably advanced relative to the drilling apparatus to repeat the pattern of drilling over the entire area of the sheets.

By holding the thin sheets of material le? and 2li together in contiguous relationship and drilling through both sheets simultaneously, the exact same pattern of holes 24 is made on both the upper sheet i8 and the lower sheet 2li. Since the sheets of material l and 2li have a thickness in the order of .020 to .062 of an inch, the drilling operation is accurate because the drills do not have a chance of going oli course as the mass through which they are drilling is quite small. The holes 24 drilled into the sheets i8 and Ztl have an axis perpendicularto the plane of the sheets and a diameter for receiving the Shanks le of needles 16.

After the holes 2d have been provided in the sheets 1S and 2l?, the sheets are separated and the needles 16 are inserted through lthe holes 24 of the upper sheet i8 as well as the corresponding holes 24 of the lower sheet 20. The needles lo, which are conventional, usually include the shank portion ll, a body portion 26 of reduced diameter having a pointed end 27 and a plurality of barbs thereon (not shown). The shank portion 14 is provided with a securing element or ear 2S which is bent substantially at ri'ht angles to the axis of the shank portion.

Gnce all ot the needles 16 have been inserted through their corresponding holes 24 in the upper and lower sheet members 1S and 2l), and the sheet members have been spaced apart a distance substantially equal to the desired thickness of the fmished needle board, one sheet member is moved or slipped relative to the other sheet member in a plane parallel of the other sheet member and all of the needles-are simultaneously oriented and aligned to a desired position. Gf course, if it is desired to have all of the needles perpendicular to the surfaces of the sheet members, then the sheet members are adjusted relative one another so that the axes of their respective holes are aligned. On the other hand, if it is desired to have some needles extending at different angles to other needles, the sheet iernbers may be arranged angularly with respect to one another. When the one sheet member 18 has been moved relative to the other sheet member 2Q a predetermined distance to obtain a'predetermiued angular relationsnip of the needles i6 to the sheet members, then the sheet members 1S and Eil are secured to a frame generally indicated at S'about their peripheral edges. ln more detail, the frame 3l) may include a plurality of channelshaped elements 32 having their legs 34 riveted to the peripheral edges of the sheets l and Zt?, indicated at 36. While the channel-shaped members 32 have been shown riveted to the sheets l and 26,V it is, of course, within the scope of the present invention that other means of securing the sheets to the trarne 3b may be accomplished such as, for example, gluing, welding, soldering or the like.

The needle board lil may be reinforced across its width or length by suitable internal stringere (not shown) either U-shaped or l-shaped in cross section, the stringers being positioned between the sheets and secured thereto after the sheets have been moved relative one another to align l and orient the needles but prior to securing the outer frame 3?. The internal stringers would, or course, be positioned between the sheets in. such a manner that they would not interfere with the needles when the needles were subsequently placed in the holes 24.

After the frame 30 has been secured and all of the needles i6 positioned in the holes 24,' the needle board is then ready for use ina needle loom. The needle board lt) is secured to a conventional clamping member 40 shown shown in broken lines in FIGURES 2 and 3. The clamping member il suitably supports the needle board lll and' also bears upon the securing elements or ears 2S of the needles lo so that they cannot be displaced along their longitudinal axis when the loom is operating, When a needle breaks or becomes worn, the needle board 10 is released from the clamping member 40 and the broken or worn needle is then easily slipped from the holes 24 in the sheets 13 and 20 and replaced by a new needle.

Another preferred form of reinforcing the needle board 1) and making it more rigid is shown in FIGURE Z'Wherein the void or space between the plates 18 and Ztl is lled with an expansible resin which is expanded in situ to form a rigid foam resin 42. This is accomplished by lling the space between the sheets 18 and Ztl with a suitable amount of the expansible resin after the sheets have been spaced apart and adjusted relative one another to orient and align the needles. The frame 3G is secured to the peripheral edges of the sheets 18 and 2t) with the resin in the space therebetween and then the composite structure with the needles in place is heated to cause the resin to expand about the Shanks of the needles and completely ll the void between the plates and the frame. The resin is cured until it becomes solidified and then the needle board is cooled. The needle board is then ready for use in the needle loom. The needles which were positioned in the holes 24 or" the sheets 18 and 2G at the time the resin was expanded and solidified and which had their shank lubricated by a silicone lubricant may be removed from the needle board if it is desired to replace the same by merely pulling the needles out by the ears 23. The needles cause a hole 44 to be molded into the needle board and, of course, when a new needle replaces the old needle, the hole 44. helps to rigidly support the shank 14 of the new needle l5.

Rigid foam resins which have proven satisfactory for the process of makingthe needle board according to theY present invention are epoxyV resins, polyurethane resins and polystyrene resins, When an epoxy resin is used, eg., a bisphenol A-epichlorhydrin resin, a powder of the epoxy resin is put into the space between the sheets as mentioned above and then heat is applied to the structure to cause the powder to liquety and expand. The expansion takes place because the resin has a blowing agent therein which reacts under heat to release a gas. After the epoxy resin has expanded and filled the void or cavity, it is cured by the application of continued heat to cause it to solidify and then the structure is cooled. When rigid polyurethane is employed, it is usually formed from two liquids, one being the urethane prepolymer, e.g., the prepolymer from glycerine-propylene oxide adduct (ruolecular'weight 1000) with a 10% excess of toluene diisocyauate, and the other being water (containing a small amount of polydimethyl soxanes and N-methyl morpholine as conventional surfactant and catalyst.) Upon the two liquids, a foam forms and rises to lill the cavity with solidified foam. Rigid polystyrene, on the other hand, is formed by placing small expansible spheres of polystyrene, the spheres having a volatile liquid in them which exapnds to form a gas when heated and which, as it is liberated, forms a porous expanded polystyrene structure.

While the above-mentioned rigid foam resins are preferable, it is, ot course, within the scope of the invention to use other rigid foam resins.

Referring now to FIGURES 4 and 5, a modified form of the present invention is disclosed. ln this form of the invention, the needle board is made only of a rigid foam resin such as the aforementioned epoxy resins, polyurethane resins or polystyrene resins. ln FIGURE 4, sleets i8 and 243 are provided with holes 24 in an identical manner to the hole 24 of the heretofore described sheets i3 and 293, the sheets l' and 2d defining a portion of a mold for the needle board itl. The sheets Ll and 2li are then spaced apart a desired distance and needles 16 are inserted through the corresponding holes 24 in the respective sheets. After the array oi needles have been inserted, the sheets 1S and Ztl are moved relative to each other to orient and align the needles as heretofore described. Then side members 32 fornnr'rg the sides or the mold are placed around the peripheral edges of the sheets and temporarily secured thereto. The internal surfaces 59 of the sheets 18 and 29' as Well as the internal surfaces 52 of the side members 32' are coated with a silicone lubricant, eg., polydirnethylsiloxme. A suitable amount of the foam resin is placed in the cavity of the mold and then the mold is subjected to heat to cause the resin to expand and solidify. After the resin has solidied and prior to disassembly of the mold, all of the needles 16 are removed leaving holes 55 in the rigid foam resin needle board 1.9', the holes having their axes properly oriented and aligned. Once the needles have been removed from the mold, the mold may be disassembled by removing the side members 32 and the sheets 1S and Ztl'. The silicone lubricant prevents the sheets 18' and 2d as Well as the side members 32 from sticking to the formed needle board 1Q. It may also be desirable to coat the shanks of the needles with the silicone lubricant so they can be removed easily.

As shown in FIGURE 5, the needles 16 are then reinserted through the holes S6 in the needle board 10' and the needle board is then clamped to the conventional clamping member 4t? of the needle loom.

It will now be seen that the needle board and the method of making the same accomplishes the objects and advantages as heretofore described. While a preferred needle board is illustrated and described, the needle board is susceptible to some changes and modifications without departing from the spirit or scope of the invention. Therefore, the terminology in this specication is for the purpose of description and not limitation, the scope of the invention being defined in the claims.

What is claimed is:

l. A needle board for use in a needle loom comprising two sheets of relatively still material having a thickness in the range of .020 to .G62 inch, each of said sheets having an identical pattern of holes therethrough, the pattern of holes or" one sheet being offset out of alignment with the pattern of holes of the other sheet, means to support said sheets in spaced apart relationship, and a plurality oi needles, said needles extending through corresponding holes in the two sheets of material.

2. A needle board as deiined in claim l including a filler means between said two sheets or" material, said filler means being a rigid foam resin.

3. A nee '.le board for use in a needle loom, said needle board comprising a body member made from a rigid foam resin and having a desired pattern of holes molded therein, and a plurality of needles held in the holes oi said body member.

4. A needle board as defined in claim 3 including a thin relatively stiff sheet covering each of the outer surfaces of the rigid foam resin body member, each sheet having a pattern of holes therein aligning with the ends oi the holes in the rigid foam resin body member; and means to secure the peripheral edges of said sheets together.

References Cited in the iile of this patent UNlTED STATES PATENTS 

1. A NEEDLE BOARD FOR USE IN A NEEDLE LOOM COMPRISING TWO SHEETS OF RELATIVELY STIFF MATERIAL HAVING A THICKNESS IN THE RANGE OF .020 TO .062 INCH, EACH OF SAID SHEETS HAVING AN IDENTICAL PATTERN OF HOLES THERETHROUGH, THE PATTERN OF HOLES OF ONE SHEET BEING OFFSET OUT OF ALIGNMENT WITH THE PATTERN OF HOLES OF THE OTHER SHEET, MEANS TO SUPPORT SAID SHEETS IN SPACED APART RELATIONSHIP, AND A PLURALITY OF NEEDLES, SAID NEEDLES EXTENDING THROUGH CORRESPONDING HOLES IN THE TWO SHEETS OF MATERIAL. 